MILWAUKEE - Steven Matz's long and winding road to the major leagues ends Friday at Citi Field, where the Mets intend to officially announce his promotion from Triple-A Las Vegas, sources confirmed Thursday.

FoxSports.com first reported the news about Matz, the last of the Mets' talented stable of starting pitchers to be promoted.

Matz, 24, who was born in Stony Brook and starred for Ward Melville High School, likely will start Sunday afternoon against the Cincinnati Reds, according to sources, with the Mets again prepared to go into a six-man starting rotation to limit the innings thrown by their promising young starters.

"We'll talk about the rotation tomorrow," said manager Terry Collins, who refused to divulge details.

Nevertheless, sources said that Matz was informed of the promotion Thursday afternoon.

Matz's promising career had barely started when he underwent Tommy John surgery in 2010, delaying his pro debut until 2012. He endured a harrowing rehab that threatened to deprive him of his chance at the major leagues, all before he set about restoring his reputation as a top pitching prospect.

Undaunted, he toiled in the minor leagues, gaining momentum as he worked toward finishing off a long journey.

When he finally stepped on a minor-league mound, Matz quickly made up for lost time.

In four minor-league seasons, he has a 2.28 ERA, 1.16 WHIP, .227 batting average against and 380 strikeouts in 3661/3 innings.

He led Double-A Binghamton to the Eastern League title in 2014, taking a no-hit bid deep into the clinching game. Matz is 7-4 with a 2.19 ERA in 15 games for Triple-A Las Vegas this season in the notoriously hitter-friendly Pacific Coast League.

Scouts have raved about his fastball command and the development of his curveball and changeup. A scout who saw Matz recently said: "He's ready to come up and slot himself with the other young guns.''

Matz has allowed six home runs this season, all of which came in his last eight starts. He last pitched on Tuesday, striking out eight in five innings and allowing three runs (two earned).

"He has dominated at every level,'' said Noah Syndergaard, the electrifying righthander who was called up earlier this year. "He did it last time I was in Vegas. And he's been continuing to do just that.''

Matz has had his pitch count lowered and closely monitored for his last several starts in preparation for a promotion.

He came close once before. According to sources, the Mets quietly reshuffled Matz's pitching schedule earlier this season when Dillon Gee went down with an injury. But the club instead chose to promote Syndergaard, partly as a nod to his experience advantage in Triple-A.

At the time, Syndergaard said it wouldn't be long before Matz would join him in the big- league rotation.

"He attacks the strike zone,'' Syndergaard said. "He has three plus pitches that he can throw at any time and get results. He's got lights-out stuff.''

Matz and Syndergaard are the latest to graduate from the Mets' pitching-rich farm system that produced Jacob deGrom in 2014, Zack Wheeler in 2013 and Matt Harvey in 2012. "The big key to pitching to major-league hitters is one, getting ahead; two, filling the strike zone up, and three, being unpredictable,'' Syndergaard said of Matz. "He does all three of those.''